Reading Notes Week 10 (November 10)

Bergholz, XML Tutorial
The article by Andre Bergholz is the clearest of all assigned articles, and I understood the other articles better after reading it. I really liked that he included examples, and also used library catalog examples, so you can see how it is applied in the library environment. It is, however, somewhat dated (from 2000), so it would be nice to read an up-to-date version of this on xml.
-- makes clear that html is layout oriented, whereas xml is structure oriented
-- both sgml and html influenced the development of xml
-- xml is about meaningful annotation
-- syntactically, xml looks like html
-- well formed document begins with prologue and has one element, and additional number of instructions can be added
-- dtds define the structure of xml documents
-- dtd elements can be nonterminal or terminal
-- elements can have zero or more attributes
-- extensions to xml include namespaces and addressing and linking capabilities
-- namespaces and dtds do not work well together
-- in html, links only point to a document
-- html is one-way
- xml extends htmls linking capacities
-- extended links connect more than one document
-- there is also an extensible stylesheet language, two languages: a transformation language and a formatting language
-- dtds have disadvantages and xml schemas address these disadvantages
-- xml schemas is well formed xml
-- the goal is to replace dtds
-- development of rdfs and doms also affect xml

Ogbuji, A Survey of XML Standards
--The world of XML is growing, with a huge variety of standards and technologies that interact in complex ways.
-- Points out that it can be difficult for beginners to navigate the most important aspects of XML, and for users to keep track of new entries and changes in the space
--includes a list of resources, if we want to explore this in more detail

XML Schema Tutorial
--XML Schemas are successors of DDT (document type definition)
--XML Schemas secure data communications
--they are extensible
--the schema element is rot of every schema
--xml schemas define elemnst of xml files
--attributes are complex
--restrictions on attributes are facets
--a complex element contains other elements or attributes
Martin Bryan. Introducing the Extensible Markup Language (XML)

This article was very difficult to follow for a non-programmer. What I understood from it, however, was that xml defines the structure of a document, rather than its appearance (like html). Therefore, xml is ideal for databases, so it can pull different elements from different locations together. “By storing data in the clearly defined format provided by XML you can ensure that your data will be transferable to a wide range of hardware and software environments. New techniques in programming and processing data will not affect the logical structure of your document's message.”